The invention is based on an apparatus for producing bag packages having dispensing fitments. Apparatuses of this kind are already known (German Pat. Document A No. 1 536 019, U.S. Pat. No. 3,894,481), in which the dispensing fitment is mounted with its flange on the outside of the bag package and is heat sealed to it. Aside from the fact that the rim of the flange offers a ready opportunity for the dispensing fitment to be torn off, it is disadvantageous for the flange to the fastened to the outside of the package because the outside of the packaging material has to be coated in a heat sealable manner, and because it takes a relatively long time to heat seal the flange of the dispensing fitment to the tube, since the heat needed for heat-sealing has to be conducted through the thick flange and then removed again after heat sealing.